SAN FRANCISCO — The NFL has taken an aggressive stance against an employment suit filed by Oakland Raiders cheerleaders, arguing the football league is exempt from claims brought under California labor law.

Plaintiffs sued the National Football League in June, accusing the franchise of conspiring to depress cheerleaders’ wages. The NFL forbid its female athletes from discussing their compensation with one another and prevented them from being hired by other NFL clubs, according to the complaint filed by Drexel Bradshaw and Clinton Woods of Bradshaw & Associates.